Appliance Running Cost Calculator

Work out what any electrical appliance costs to run per hour, day, month and year, starting from the current Ofgem price cap rate.

Reviewed by Dany, RightSums team · Updated

Runs in your browser. Free, no sign-up.

home-energy · Daily life · UK & US

Pick an appliance or type in its wattage, say how long you use it, and the calculator shows the energy it uses and what that costs. The unit rate starts at the Ofgem price cap for Direct Debit customers, and you can change it to the rate on your own bill. Presets use the Centre for Sustainable Energy's average power ratings, with usage for washing machines, dryers and fridges matched to Which? test data.

Accepted inputs

  • Appliance or wattage
  • Hours used a day
  • Days used a week
  • Unit rate per kWh

Outputs

  • kWh used
  • Cost per day
  • Cost per week
  • Cost per month
  • Cost per year

How to use the Appliance Running Cost Calculator

  1. Choose an appliance from the list, or enter the wattage from its label or rating plate.
  2. Enter how many hours a day you use it and how many days a week.
  3. Check the unit rate. It starts at the Ofgem price cap; change it to the rate on your bill if you are on a fixed deal.
  4. Read off the kWh used and the cost per day, week, month and year.

Frequently asked questions

How do I work out what an appliance costs to run?

Divide the wattage by 1,000 to get kilowatts, multiply by the hours it is on, then multiply by your unit rate. A 2,000 W heater running for 3 hours uses 6 kWh, which costs about £1.58 at 26.32p per kWh.

What unit rate should I use?

Use the rate on your bill or in your supplier's app. If you are on a standard variable tariff, the Ofgem price cap sets the average rate, and the calculator starts from that figure.

Why does my washing machine cost less than wattage times hours?

Appliances with heating elements, such as washing machines, dishwashers and ovens, only draw full power while they are heating. For those, the presets are set to match the energy Which? measured in testing rather than full power for the whole cycle.

Does this include the standing charge?

No. The standing charge is a fixed daily amount you pay whatever you use, so it does not change with how much you run an appliance.

Guides that use this tool

Terms explained

  • Economy 7: Economy 7 is an electricity tariff with seven cheaper off-peak hours, usually overnight, and a dearer daytime rate; Ofgem assumes 42% of use falls off-peak.
  • Energy price cap: The energy price cap is Ofgem’s limit on unit rates and standing charges for default tariffs; typical bill £1,723 from 1 October 2026.
  • Standing charge: A standing charge is the fixed daily amount on an energy bill, paid whatever you use; the capped average is 54.83p a day for electricity.
  • Typical domestic consumption values (TDCVs): Typical domestic consumption values are Ofgem's yearly usage figures for a typical home, 2,500 kWh electricity and 9,500 kWh gas from 1 July 2026.

Running costs by appliance

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